Extensible carpenter&#39;s level

ABSTRACT

The present invention is an extensible carpenter&#39;s level that is adjustable between a collapsed position and a fully-extended position. The level may be manufactured in a variety of sizes. An exemplary embodiment of the level is comprised of an innerslide and two outerslides. The innerslide has two sets of tracks or tongues. Each of the outerslides is slidably connected to the innerslide. In particular, one outerslide is adapted to slide along one set of tracks or tongues, and the other outerslide is adapted to slide along the other set of tracks or tongues. At least one of the slides includes at least one level bubble. The level preferably includes multiple level bubbles to enable a variety of measurements, e.g., a horizontal level, a vertical level, and a 45° level.

This application is a continuation-in-part of U.S. application Ser. No.09/329,871, filed Jun. 11, 1999, now U.S. Pat. No. 6,279,240, whichclaims the benefit of U.S. Provisional Application No. 60/089,099, filedJun. 12, 1998.

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates generally to a carpenter's level, and moreparticularly, to an extensible carpenter's level. A carpenter's levelmay be used to determine the angular position of a given plane orsurface relative to a reference plane or surface. A carpenter's levelgenerally includes a level bubble mounted in a housing. The level bubbleis mounted in the housing at a predetermined orientation relative to areference edge of the housing. As a result, the angular position of asurface may be determined by placing the reference edge of the housingagainst the surface.

In order to achieve optimum accuracy, the length of the reference edgeof the housing is preferably about equal to the length of the surface tobe checked. If the reference edge is too short, the carpenter's levelmay be overly sensitive to undulations in the surface. On the otherhand, the carpenter's level may be unnecessarily cumbersome if it is toolong. Consequently, it is often necessary to have carpenter's levels ofvarying lengths for a particular job.

Extensible carpenter's levels have been advanced in an attempt toeliminate the need to carry several carpenter's levels of varyinglengths. However, known extensible carpenter's levels are unnecessarilycomplicated and expensive to manufacture. Consequently, a need existsfor a stable, extensible carpenter's level which is easy to use andmanufacture.

The present invention provides an improved extensible carpenter's levelwhich is slidably adjustable between a collapsed position and afully-extended position. The reference edges of the level remainsubstantially aligned in the same plane regardless of the position ofthe level. An exemplary embodiment of the level includes an innerslide,a first outerslide, and a second outerslide. The innerslide has a firstset of tracks and a second set of tracks. The outerslides are slidablyconnected to the innerslide. The first outerslide and the secondouterslide are preferably adapted to slide independently each other. Thefirst outerslide is adapted to slide along the first set of tracks, andthe second outerslide is adapted to slide along the second set oftracks. At least one of the slides includes at least one level bubble.Different types of level bubbles may be mounted in the same level toallow for a variety of measurements. For example, one level may includea horizontal level bubble, a vertical level bubble, and a level bubblethat measures a predetermined angle, e.g., 30°.

The cross section of the innerslide may be generally I-shaped. The firstset of tracks is preferably comprised of a first track on a top side ofthe innerslide and a second track on a bottom side of the innerslide. Inaddition, the second set of tracks is preferably comprised of a thirdtrack on the top side of the innerslide and a fourth track on the bottomside of the innerslide. However, it should be recognized that the levelmay have any appropriate number of tracks located in any appropriatepositions on the innerslide.

The first outerslide is preferably comprised of a first extension memberwhich is connected to a first end member. The first extension member maybe longer than the first end member. The first extension memberpreferably has a first tongue which is adapted to slide in the firsttrack and a second tongue which is adapted to slide in the second track.On the other hand, the first end member preferably has a third tonguewhich is adapted to slide in the third track and a fourth tongue whichis adapted to slide in the fourth track. The second outerslide ispreferably similar to, but opposing, the first outerslide. The secondouterslide is preferably comprised of a second extension member which isconnected to a second end member. The second extension member may belonger than the second end member. The second extension memberpreferably has a fifth tongue and a sixth tongue, wherein the fifthtongue is adapted to slide in the third track and the sixth tongue isadapted to slide in the fourth track. Furthermore, the second end memberpreferably has a seventh tongue which is adapted to slide in the firsttrack and an eighth tongue which is adapted to slide in the secondtrack. The first extension member preferably abuts the second end memberand the second extension member preferably abuts the first end memberwhen the carpenter's level is in the collapsed position.

The level may be magnetized. For example, any of the slides may be madefrom a magnetized material. For another example, one or more magnets maybe secured to any of the slides. Preferably, a magnetic strip is adheredto a reference edge of the level. Magnetization preferably helps to holdthe reference edge of the level securely against an appropriate surface,e.g., a metal surface, that is being measured. It also preferably helpsto prevent the level from falling off a suitable surface during ameasurement.

The carpenter's level preferably includes means for releasably lockingthe position of at least one of the outerslides relative to theinnerslide at predetermined intervals. This feature preferablyfacilitates the use of the level at intermediate lengths between thecollapsed position and the fully-extended position. The means may be aspring-loaded ball bearing or pin that is releasably engaged by grooves,cutouts, or notches that are spaced at predetermined intervals on theinnerslide or either of the outerslides. It may be preferred that a usercan disengage the spring-loaded ball bearing or pin by sliding theouterslide relative to the innerslide.

Another embodiment of the level is similar to the embodiment describedabove except that the innerslide has tongues. In this embodiment, theinnerslide has a first set of tongues and a second set of tongues. Thefirst outerslide is slidably connected to the innerslide, and it isadapted to slide along the first set of tongues. The second outerslideis also slidably connected to the innerslide, and it is adapted to slidealong the second set of tongues. At least one of the slides includes atleast one level bubble.

The first set of tongues may be comprised of a first tongue on a topside of the innerslide and a second tongue on a bottom side of theinnerslide. The second set of tongues may be comprised of a third tongueon the top side of the innerslide and a fourth tongue on the bottom sideof the innerslide. In such an embodiment, the first outerslidepreferably has a first extension member which is connected to a firstend member, and the second outerslide preferably has a second extensionmember which is connected to a second end member. The first extensionmember has a first track which is adapted to slide along the firsttongue and a second track which is adapted to slide along the secondtongue. The first end member has a third track which is adapted to slidealong the third tongue. The first end member also has a fourth trackwhich is adapted to slide along the fourth tongue. On the other hand,the second extension member has a fifth track which is adapted to slidealong the third tongue and a sixth track which is adapted to slide alongthe fourth tongue. Furthermore, the second end member has a seventhtrack which is adapted to slide along the first tongue and an eighthtrack which is adapted to slide along the second tongue.

This embodiment may also include the optional and preferred features ofthe first embodiment.

In addition to the novel features and advantages mentioned above, otherobjects and advantages of the present invention will be readily apparentfrom the following descriptions of the drawings and exemplaryembodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a first exemplary embodiment of anextensible carpenter's level of the present invention;

FIG. 2A is a top plan view of the level of FIG. 1;

FIG. 2B is a cross section view along A—A of FIG. 2A;

FIG. 2C is a cross section view along B—B of FIG. 2A;

FIG. 3A is a side elevation view of the level of FIG. 1;

FIG. 3B is an elevation view of the left end of the level of FIG. 3A;

FIG. 3C is a cross section view along C—C of FIG. 3A;

FIG. 4A is a side elevation view of an outerslide of the level of FIG.1;

FIG. 4B is an elevation view of the right end of the outerslide of FIG.4A;

FIG. 5 is a bottom plan view of the outerslide of FIG. 4A;

FIG. 6A is another side elevation view of the outerslide of FIG. 4A;

FIG. 6B is an elevation view of the left end of the outerslide of FIG.6A;

FIG. 7A is a side elevation view of the innerslide of the level of FIG.1;

FIG. 7B is an elevation view of the left end of the innerslide of FIG.7A;

FIG. 8A is a side elevation view of an extension member of theouterslide of FIG. 4A;

FIG. 8B is an elevation view of the left end of the extension member ofFIG. 8A;

FIG. 9A is a side elevation view of an end member of the outerslide ofFIG. 4A;

FIG. 9B is an elevation view of the left end of the end member of FIG.9A;

FIG. 10A is a side elevation view of an outerslide mounting assembly fora level bubble of the level of FIG. 1;

FIG. 10B is an elevation view of an end cap of the outerslide mountingassembly of FIG. 10A;

FIG. 10C is a cross section view along A—A of FIG. 10B;

FIG. 10D is a cross section view along B—B of FIG. 10C;

FIG. 10E is a cross section view along C—C of FIG. 10D;

FIG. 11A is a side elevation view of a vial housing which is adapted tobe mounted in the outerslide mounting assembly of FIG. 10A;

FIG. 11B is an elevation view of the right end of the vial housing ofFIG. 11A;

FIG. 11C is a cross section view along A—A of FIG. 11B;

FIG. 12A is an elevation view of an end of a vial housing mate for thevial housing of FIG. 11A;

FIG. 12B is a cross section view along A—A of FIG. 12A;

FIG. 13A is a side elevation view of a vial housing which is adapted tobe mounted on the innerslide of the level of FIG. 1;

FIG. 13B is an elevation view of an end of the vial housing of FIG. 13A;

FIG. 13C is a cross section view along A—A of FIG. 13B;

FIG. 13D is a cross section view along B—B of FIG. 13B;

FIG. 14A is an end elevation view of an optional track member of theinnerslide of the level of FIG. 1;

FIG. 14B is a side elevation view of the optional track member of FIG.14A;

FIG. 15A is a side elevation view of a plunge block of the level of FIG.1;

FIG. 15B is an elevation view of the left end of the plunge block ofFIG. 15A;

FIG. 15C is a cross section view along A—A of FIG. 15A;

FIG. 16A is a side elevation view of a stop of the level of FIG. 1;

FIG. 16B is a cross section view along A—A of FIG. 16A;

FIG. 16C is an elevation view of an end of the stop of FIG. 16A;

FIG. 17 is a perspective view of a second exemplary embodiment of alevel of the present invention in a fully-extended position;

FIG. 18 is a cross section view of a third exemplary embodiment of alevel of the present invention;

FIG. 19 is a side elevation view of a fourth exemplary embodiment of alevel of the present invention;

FIG. 20 is a perspective view of a fifth exemplary embodiment of anextensible carpenter's level of the present invention;

FIG. 21 is a side elevation view of the level of FIG. 20;

FIG. 22 is a top plan view of the level of FIG. 20;

FIG. 23 is an end elevation view of the level of FIG. 20; and

FIG. 24 is a perspective view of the level of FIG. 20 in an openposition.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENT(S)

The present invention is directed to an improved extensible carpenter'slevel which is slidably adjustable between a collapsed position and afully extended position. FIGS. 1, 2A-2C, and 3A-3C illustrate anexemplary embodiment of the extensible carpenter's level 10 in acollapsed position. FIGS. 4A-4B, 5, 6A-6B, 7A-7B, 8A-8B, 9A-9B, 10A-10E,11A-11C, 12A-12B, 13A-13D, 14A-14B, 15A-15C, 16A-16C illustrate variousviews of the components of the level 10. In this embodiment, the level10 includes an innerslide 20, a first outerslide 30, and a secondouterslide 40. The first outerslide 30 and the second outerslide 40 areslidably connected to the innerslide 20. In addition, the reference edge32 of the first outerslide 30 and the reference edge 42 of the secondouterslide 40 remain substantially aligned in the same plane regardlessof the position of the extensible carpenter's level 10.

The slides 20, 30, 40 may be made from any suitable material. Forexample, the slides 20, 30, 40 may be from metal (e.g., aluminum, steel,or other metals), plastic, or wood. In addition, the slides 20, 30, 40may be manufactured using any appropriate technique, e.g., extrusion ormolding.

In this embodiment, the first outerslide 30 abuts against the secondouterslide 40 in the collapsed position. The first outerslide 30 and thesecond outerslide 40 may be slid independently of one another. Theinnerslide 20 has a first and second set of tracks. FIG. 7B most clearlyshows the tracks. The first set of tracks is comprised of track 22 andtrack 24, and the second set of tracks is comprised of track 26 andtrack 28. The first outerslide 30 and the second outerslide 40 havetongues that are adapted to slide in the tracks 22, 24, 26, 28. FIG. 4Bshows the tongues 52, 54, 56, 58 of one outerslide. The tongues 52, 54,56, 58 are adapted to slide in the tracks 22, 24, 26, 28. It should beunderstood that the tongues 52, 54, 56, 58 can slide in the tracks 22,24, 26, 28 with or without making contact with the tracks 22, 24, 26,28. By pulling on opposite ends of the level 10, a user can cause theouterslides 30, 40 to slide in opposite directions relative to theinnerslide 20 such that the level 10 moves from the collapsed positioninto a fully extended position.

FIGS. 14A-14B show an optional track member 60 which may be inserted inthe tracks 22, 24, 26, 28. An exemplary embodiment of the track member60 slidably mates with a corresponding tongue so that the level 10 isstable when it is being adjusted from one position to another. A trackmember 60 may be secured in each of the tracks 22, 24, 26, 28 byconventional means, e.g., by mechanical fastening means such as screws,pins, clamps, or rivets, by an adhesive, or by any other suitable means.In an alternative embodiment, a track member 60 may be integral to theinnerslide 20. FIGS. 2B, 2C, and 3C show an exemplary relationshipbetween the track members 60 and the tongues of the outerslides 30, 40.A track member 60, whether integral to an outerslide or a separatecomponent, may be made from any suitable material such as metal (e.g.,aluminum, steel, or other metals), plastic (e.g., TEFLON plastic or anyother similar or suitable plastic materials), or wood.

In addition, the extensible carpenter's level 10 may be extendible inincrements between a collapsed position and a fully extended position.The extensible carpenter's level 10 may include at least one lockingdevice which is adapted to releasably lock the position of at least oneof the outerslides 30, 40 relative to the innerslide 20 at predeterminedintervals between the collapsed position and the fully-extendedposition. An example of a locking device comprises a spring-loaded ballbearing, pin, plunger, or any other suitably-shaped object which isreleasably engaged by grooves, notches, or cutouts spaced atpredetermined intervals on the innerslide 20 or one of the outerslides30, 40. FIGS. 15A-15B show various views of an exemplary embodiment of aplunge block 70. The plunge block 70 includes a chamber 72 which isadapted to house a spring-loaded ball bearing, pin, etc. In thisembodiment, a plunge block 70 is secured to each side of the innerslide20 via screws or rivets which extend through hole 74 and hole 76 of eachplunge block 70. FIGS. 1, 3A, and 7A show corresponding holes 80, 82,84, 86 that receive the screws or rivets from the plunge blocks 70. Itshould also be recognized that a plunge block 70 may be secured to theinnerslide 20 or an outerslide by any other appropriate means, e.g., byany other mechanical fastening means, by an adhesive, or by any othersimilar, suitable, or conventional means. FIGS. 4A and 8A show thenotches 78 of one outerslide which are adapted to releasably engage arespective spring-loaded ball bearing as the outerslide slides relativethe innerslide 20.

At least one of the slides has a level bubble the innerslide 20, thefirst outerslide 30, and the second outerslide 40 may each include atleast one level bubble. In the embodiment shown in FIGS. 1, theinnerslide 20 has a level bubble 28, the first outerslide 30 has a levelbubble 38, and the second outerslide 40 has a level bubble 48. In thisexample, each of the level bubbles may be visible in all collapsed andextended positions. Moreover, the level bubbles are preferably mountedin their respective vial housings at different predeterminedorientations relative to the reference edges in order to allow a varietyof measurements. For example, one level bubble may function as ahorizontal level, a second level bubble may function as a verticallevel, and a third level bubble may function as a 45 degree level.

In order to facilitate manufacturing of the extensible carpenter's level10, the first outerslide 30 and the second outerslide 40 may besubstantially identical. In the embodiment shown in FIG. 1, the firstouterslide 30 is substantially identical to the second outerslide 40.The first outerslide 30 has an extension member 34, and the secondouterslide 40 has an extension member 44. In addition, the firstouterslide 30 may have an end member 36, and the second outerslide 40may have an end member 46.

FIGS. 4A-4B, 5, and 6A-6B illustrate an outerslide which isrepresentative of both the first outerslide 30 and the second outerslide40 of the extensible carpenter's level 10 of FIGS. 1 through 3. FIGS.8A-8B show an extension member of the outerslide of FIGS. 4A-4B, 5, and6A-6B, and FIGS. 9A-9B illustrate an end member of the outerslide ofFIGS. 4A-4B, 5, and 6A-6B. FIGS. 7A-7B show the innerslide 20 of theextensible carpenter's level 10.

FIGS. 10A-10E show an outerslide mounting assembly 90 for a levelbubble. The outerslide mounting assembly 90 includes an end cap 92. Theend cap 92 may be made of any suitable material such as metal, plastic(e.g., rubber), or any other similar or conventional material. FIGS.11A-11C show a vial housing 94, and FIGS. 12A-12B show a vial housingmate 96. Vial housing 94 and vial housing mate 96 are adapted to bemounted in the outerslide mounting assembly 90. The outerslide mountingassembly 90, vial housing 94, and vial housing mate 96 may be adapted tosecure the end members to the extension members of the outerslides.However, it should be recognized that an extension member may beintegrally connected to an end member. It should also be recognized thatan end member may be connected to an extension member in other similar,suitable, or conventional manner.

FIGS. 13A-13D show another vial housing 100 which is adapted to bemounted on the innerslide 20.

A transparent shield, e.g., glass or plastic, may extend over the vialhousings to protect the level bubbles. Also, the vial housings may beraised from, flush with, or below the surface of the outerslides.

FIGS. 16A-16C show a stop 110. Stops 110 may be adapted to abutrespective plunge blocks 70 in the fully extended position. In thisembodiment, the stops 110 are secured to the extension members byscrews, rivets, or any other mechanical fastening means through holes112. However, it should be recognized that the stops 110 may be securedto the extension members by any suitable means, e.g., integrallyconnected, by an adhesive, or in any other similar, suitable, orconventional manner.

FIG. 17 shows another embodiment of a level 120 of the present inventionin a fully extended position. The level 120 may include any of theoptional or preferred features described above.

FIG. 18 shows another embodiment of a level 130 of the present inventionin which the innerslide has tongues and the outerslides have tracks. Thelevel 130 may include any of the optional or preferred featuresdescribed above.

FIG. 19 shows yet another embodiment of a level 140 of the presentinvention in which a stop 142 extends from a top portion to a bottomportion of an extension member. The level 140 may include any of theoptional or preferred features described above.

FIGS. 20 through 24 show another example of a level 150 of the presentinvention in which a stop extends from a top portion to a bottom portionof an extension member. The level 150 may include any of theabove-described optional or preferred features. In this example, rivetsor screws 152 secure a stop 154 to an extension member 156.Nevertheless, it should be recognized that the stop 154 may be securedto the extension member 156 by any desired means including, but notlimited to, integral connection, adhesives, other mechanical fasteningmeans, or any other similar, suitable, or conventional connection orfastening means.

In this example, an end portion 158 connects the top and bottom portionsof the extension member 156. The end portion 158 may abut the endportion 160 of end member 162 when the level is in a collapsed position.The end portion 158 may define at least a portion of a cutout or opening164 of the extension member 156. As shown in the exemplary embodiment,the cutout or opening 164 may be adapted to enable a centrally locatedlevel bubble to be seen regardless of the position of the level 150.

The vial housing 166, the vial housing mate 168, and the vial housing170 may be about flush with or recessed from an outer surface 172 of theextension member 156 and an outer surface 174 of the end member 162.Such an arrangement may facilitate laying the level 150 substantiallyflat against a surface when taking a measurement or using the level 150like a ruler, e.g., using a reference edge to draw a straight line. Inthis example, the vial housing 166 is about flush with the outer surface172, and the vial housing mate 168 is about flush with the outer surface174. On the other hand, the vial housing 170 is recessed from the outersurface 172. As seen in FIG. 22, this arrangement provides the level 150with substantially flat sides.

In operation, the level 150 may be adjusted by sliding the extensionmember 156 away from the end member 162. As the members are slid apart,the stop 154 passes by an outer surface of the vial housing 170. If thesliding movement is continued, the stop 154 eventually abuts a plungeblock 176, thereby preventing further sliding movement in thatdirection.

Each end of the level 150 may include an end cap 178. The end cap 178may be comprised of any suitable material including, but not limited to,metal, plastic, wood, or any other similar, suitable, or conventionalmaterial. For example, the end cap 178 may be comprised of rubber tohelp protect the level 150 from damage in the event it is dropped.

The level 150 may have opposing lateral sides 180, 182. As in thepreviously described embodiments, each of the three level bubbles may beviewed substantially without obstruction (i.e., the readings of thelevel bubbles are visible) when looking at lateral side 180 or lateralside 182 regardless of the adjusted position of the level 150. As aresult, either side of the level 150 may be used equally well andwithout limitation. Moreover, as shown in the figures, the distanceseparating the level bubbles may be adjusted substantially withoutobstructing the view of the level bubbles from either lateral side.

Those skilled in the art will recognize that the present invention mayhave any desired dimensions (lengths, widths, heights, etc.). Forexample, the length of one embodiment of the present invention may beadjustable between 6 inches and 12 inches, and the length of anotherembodiment of the present invention may be adjustable between 4 feet and8 feet. In other words, a level of the present invention may be designedto be adjustable within any desired range.

The exemplary embodiments herein disclosed; are not intended to beexhaustive or to unnecessarily limit the scope of the invention. Theexemplary embodiments were chosen and described in order to explain theprinciples of the present invention so that others skilled in the artmay practice the invention. Having shown and described exemplaryembodiments of the present invention, those skilled in the art willrealize that many variations and modifications may be made to affect thedescribed invention. Many of those variations and modifications willprovide the same result and fall within the spirit of the claimedinvention. It is the intention, therefore, to limit the invention onlyas indicated by the scope of the claims.

What is claimed is:
 1. A level adjustable between a collapsed positionand a fully-extended position, said level comprising: an innerslidehaving a first set of tracks and a second set of tracks, said first setof tracks comprised of a first track on a top side of said innerslideand a second track on a bottom side of said innerslide, said second setof tracks comprised of a third track on said top side of said innerslideand a fourth track on said bottom side of said innerslide; a firstouterslide slidably connected to said innerslide, said first outerslideadapted to slide along said first set of tracks, said first outerslideincluding a first level bubble, said first outerslide further includinga first extension member and a first end member, said first extensionmember connected to said first end member, said first extension memberhaving a first tongue which is adapted to slide in said first track,said first extension member also having a second tongue which is adaptedto slide in said second track, said first end member having a thirdtongue which is adapted to slide in said third track, said first endmember also having a fourth tongue which is adapted to slide in saidfourth track; and a second outerslide slidably connected to saidinnerslide, said second outerslide adapted to slide along said secondset of tracks, said second outerslide including a second level bubble,said second outerslide further including a second extension member and asecond end member, said second extension member connected to said secondend member, said second extension member having a fifth tongue which isadapted to slide in said third track, said second extension member alsohaving a sixth tongue which is adapted to slide in said fourth track,said second end member having a seventh tongue which is adapted to slidein said first track, said second end member also having an eighth tonguewhich is adapted to slide in said second track; wherein the level hasopposing lateral sides; wherein the distance separating said first levelbubble from said second level bubble is adjustable; and wherein bothsaid first level bubble and said second level bubble are visiblesubstantially without obstruction from both of said lateral sidesregardless of the adjusted position of the level.
 2. The level of claim1 wherein said first extension member abuts said second end member andsaid second extension member abuts said first end member when said levelis in said collapsed position.
 3. The level of claim 1 wherein: saidfirst extension member is longer than said first end member; and saidsecond extension member is longer than said second end member.
 4. Alevel adjustable between a collapsed position and a fully-extendedposition, said level comprising: an innerslide having a first set oftongues and a second set of tongues, said first set of tongues comprisedof a first tongue on a top side of said innerslide and a second tongueon a bottom side of said innerslide, said second set of tonguescomprised of a third tongue on said top side of said innerslide and afourth tongue on said bottom side of said innerslide; a first outerslideslidably connected to said innerslide, said first outerslide adapted toslide along said first set of tongues, said first outerslide including afirst level bubble, said first outerslide further including a firstextension member and a first end member, said first extension memberconnected to said first end member, said first extension member having afirst track which is adapted to slide along said first tongue, saidfirst extension member also having a second track which is adapted toslide along said second tongue, said first end member having a thirdtrack which is adapted to slide along said third tongue, said first endmember also having a fourth track which is adapted to slide along saidfourth tongue; and a second outerslide slidably connected to saidinnerslide, said second outerslide adapted to slide along said secondset of tongues, said second outerslide including a second level bubble,said second outerslide further including a second extension member and asecond end member, said second extension member connected to said secondend member, said second extension member having a fifth track which isadapted to slide along said third tongue, said second extension memberalso having a sixth track which is adapted to slide along said fourthtongue, said second end member having a seventh track which is adaptedto slide along said first tongue, said second end member also having aneighth track which is adapted to slide along said second tongue; whereinthe level has opposing lateral sides; wherein the distance separatingsaid first level bubble from said second level bubble is adjustable; andwherein both said first level bubble and said second level bubble arevisible substantially without obstruction from both of said lateralsides regardless of the adjusted position of the level.
 5. The level ofclaim 4 wherein said first extension member abuts said second end memberand said second extension member abuts said first end member when saidlevel is in said collapsed position.
 6. The level of claim 4 wherein:said first extension member is longer than said first end member; andsaid second extension member is longer than said second end member.